The invention relates to a device for lowering a load, for example, a diving bell from a vessel from a spot above the water line to a spot beneath the water line, said device comprising a winch and a cable connected with the load and moved by said winch along at least one cable pulley rotatable about a shaft. When the load comes into contact with the water, the problem occurs that due to heaving of the vessel the cable becomes alternately slack and taut. It may, therefore, occur, that when the cable is slack the load is solely subjected to the wash of the waves and to other movements of the water so that the load may perform unpredictable motions. Especially in the case of a diving bell this is very troublesome, since the persons therein are exposed to strong, very disagreeable movements, for example, when the diving bell tilts. Particularly in the case of a rough sea this problem is serious. The solution of this problem is rendered difficult, since the force exerted by the load on the cable gradually decreases after traversing the water line due to the upward pressure exerted on the load by the water. In the case of non-solid objects, for example, a diving bell, this change is appreciable. When the load is fully immersed, the problem is simplified to an extent such that only the heaving of the vessel has to be taken into account.